1. Field of Invention
The present invention relates to a connection structure, and more particularly to a symmetrical joint structure for connecting two physical matters together to form a strong and integral body that minimizes the stress of the connecting parts thereof.
2. Description of Related Arts
Joint structure is the most common way to connect two physical matters together in various fields such as mechanical structure, civil construction, biological engineering, and etc. All building constructions need to connect beams end to end coaxially. Transmission shaft is generally made by coaxially connecting two axles end to end together. Any beam made of two or more kinds of material also need to connect sections together through joint structure. Even a branch can be coaxially joined with another branch of another species to form a new species.
FIG. 1A illustrates a most common joint A for connecting two ends A11, A21 of two beams A1, A2 coaxially together, wherein a radial slot A12 is formed at one end A11 of the first beam A1 while a narrowed latch A22 is formed at one end A21 of the second beam A2. By fittedly inserting the latch A22 into the slot A12, the second beam A2 can be joined with the first beam A1 to form an elongated beam.
FIG. 1B illustrates another common joint B for connecting two ends B11, B21 of a first and a second beam B1, B2 coaxially together, wherein each end B11, B21 of the first and second beams B1, B2 forms a semi-circular latch B12, B22, so that by overlappingly connecting the two semi-circular latches B12, B22 together, the first and second beams B1, B2 can also be joined to form an elongated beam.
FIG. 1C illustrates another common joint C for connecting two ends C11, C21 of a first and a second beam C1, C2 coaxially together, wherein a central latch C12 is formed at one end C11 of the first beam C1 while a central hole C22 is formed at one end C21 of the second beam C2. By fittedly inserting the central latch C12 into the central hole C22, the second beam C2 can be joined with the first beam C1 to form an elongated beam.
FIG. 1D illustrates one more common joint D for connecting two ends D11, D21 of first and a second beam D1, D2 coaxially together, wherein a connecting ring D12, D22 is formed at each end D11, D21 of the two beams D1, D2. By connecting the two connecting rings D12, D22 together, the first and the second beams D1, D2 can be coaxially connected together to form an elongated beam.
However, when a torque is applied to each of such elongated beams as disclosed above, the high intensity stress formed at those connecting parts, such as the connecting corners of the latch A22 and slot A12, the two semi-circular latches B12, B22, the central latch C12 and the central hole C22, and the two connecting rings D12, D22, would weaken the joint A, B, C, or D. Moreover, if the first beam A1, B1, C1, or D1 is a driving axle and the second beam A2, B2, C2, or D2 is a driven axle, friction will form between all contacting flat surfaces.
Like a two-piece golf ball, when a spherical core is required to be constructed by joining two semi-spherical halves E1, E2 together to form a spheroid E, as shown in FIG. 2, the biggest problem is how to minimize the friction and torque formed therebetween during rotation and impact. Even applying extra strong adhesive between the two attaching surfaces, such combined spheroid E is still weak for torque.
The main objective of the present invention is to provide a symmetrical joint structure for physical matter connection, wherein two identical joint portions of two objects can be united together with minimum friction between the contacting surfaces and minimized stress occurred at the connecting joint portions.
Another objective of the present invention is to provide a symmetrical joint structure which can be apply for constructing a spheroid by two symmetrical pieces while minimizing the friction between all contacting surfaces and the stress of all connecting portions during rotation and impact.
Another objective of the present invention is to provide a symmetrical joint structure which can apply for joining two ends of two beams coaxially together while minimizing the friction between all contact surfaces and the stress of all connecting portions.
Another objective of the present invention is to provide a symmetrical joint structure, wherein the two joint portions of two physical matters are symmetrically identical that each provides a curved and smooth joint surface so as to enable the two joint portions to fittingly engage with each other integrally.
Another objective of the present invention is to provide a symmetrical joint structure adapted for perfectly and firmly connecting two physical matters together in such a manner that the united physical matters cannot be separated in all direction except separating the two physical matters coaxially apart, so that the symmetrical joint structure is good for power transmission that, for example, if one of the physical matters is a driving object and the other physical matter is a driven object, the rotation of the driving object can be completely transmitted to the driven object and drive it to rotate accordingly.
In order to accomplish the above objectives, the present invention provides a symmetrical joint structure for integrally joining a first joint element and a second joint element together;
wherein the first joint element has a first joint portion which comprises two identical first semi-conical engagement tongues symmetrically projecting at two sides thereof so as to define two identical first semi-conical engagement grooves symmetrically indented between the two first semi-conical engagement tongues, wherein the two first semi-conical engagement tongues respectively define two first conically curved tongue surfaces symmetrically facing with each other, and the two first semi-conical engagement grooves respectively define two first conically curved groove surfaces symmetrically and continuously extended between the two first conically curved tongue surfaces so as to form a continuous first joint surface for the first joint portion;
wherein the second joint element has a second joint portion which comprises two identical second semi-conical engagement tongues symmetrically projecting at two sides thereof so as to define two identical second semi-conical engagement grooves symmetrically indented between the two second semi-conical engagement tongues, wherein the two second semi-conical engagement tongues respectively define two second conically curved tongue surfaces symmetrically facing with each other, and the two second semi-conical engagement grooves respectively define two second conically curved groove surfaces symmetrically and continuously extended between the two second conically curved tongue surfaces so as to form a continuous second joint surface for the second joint portion;
wherein a cone height of each of the first and second semi-conical engagement tongues is equal to a cone height of each of the first and second semi-conical engagement grooves, and thus the size and shape of the first joint portion and the second joint portion are identical and symmetrical, wherein the two second semi-conical engagement tongues are fittingly engaged in the two first semi-conical engagement grooves respectively while the two first semi-conical engagement tongues are fittingly engaged in the two second semi-conical engagement grooves respectively, so as to integrally united the first joint portion and the second joint portion together to form the symmetrical joint structure.